X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/df31b1fd5b0bfbf02a766d32e23a7af075bf4911..cda88cf97c63c26229578e17184bedcdc0cabc77:/Projects/AVRISP/Lib/PDITarget.c

diff --git a/Projects/AVRISP/Lib/PDITarget.c b/Projects/AVRISP/Lib/PDITarget.c
index 29bb33985..2c6ffd9a6 100644
--- a/Projects/AVRISP/Lib/PDITarget.c
+++ b/Projects/AVRISP/Lib/PDITarget.c
@@ -67,13 +67,13 @@ ISR(TIMER1_COMPA_vect, ISR_BLOCK)
 		  return;
 		  
 		/* Wait for the start bit when receiving */
-		if ((SoftUSART_BitCount == BITS_IN_FRAME) && (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK))
+		if ((SoftUSART_BitCount == BITS_IN_PDI_FRAME) && (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK))
 		  return;
 	
 		/* Shift in the bit one less than the frame size in position, so that the start bit will eventually
 		 * be discarded leaving the data to be byte-aligned for quick access */
 		if (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK)
-		  SoftUSART_Data |= (1 << (BITS_IN_FRAME - 1));
+		  SoftUSART_Data |= (1 << (BITS_IN_PDI_FRAME - 1));
 
 		SoftUSART_Data >>= 1;
 		SoftUSART_BitCount--;
@@ -133,6 +133,7 @@ void PDITarget_EnableTargetPDI(void)
 	TCCR1B  = (1 << WGM12) | (1 << CS10);
 	TIMSK1  = (1 << OCIE1A);
 	
+	/* Send two BREAKs of 12 bits each to enable TPI interface (need at least 16 idle bits) */
 	PDITarget_SendBreak();
 	PDITarget_SendBreak();
 #endif
@@ -158,8 +159,6 @@ void PDITarget_DisableTargetPDI(void)
 	/* Tristate DATA and CLOCK lines */
 	BITBANG_PDIDATA_PORT  &= ~BITBANG_PDIDATA_MASK;
 	BITBANG_PDICLOCK_PORT &= ~BITBANG_PDICLOCK_MASK;
-
-	TCCR0B  = 0;
 #endif
 }
 
@@ -212,7 +211,7 @@ void PDITarget_SendByte(const uint8_t Byte)
 
 	/* Data shifted out LSB first, START DATA PARITY STOP STOP */
 	SoftUSART_Data     = NewUSARTData;
-	SoftUSART_BitCount = BITS_IN_FRAME;
+	SoftUSART_BitCount = BITS_IN_PDI_FRAME;
 #endif
 }
 
@@ -254,7 +253,7 @@ uint8_t PDITarget_ReceiveByte(void)
 	}
 
 	/* Wait until a byte has been received before reading */
-	SoftUSART_BitCount = BITS_IN_FRAME;
+	SoftUSART_BitCount = BITS_IN_PDI_FRAME;
 	while (SoftUSART_BitCount);
 	
 	/* Throw away the parity and stop bits to leave only the data (start bit is already discarded) */
@@ -279,7 +278,7 @@ void PDITarget_SendBreak(void)
 	}
 
 	/* Need to do nothing for a full frame to send a BREAK */
-	for (uint8_t i = 0; i < BITS_IN_FRAME; i++)
+	for (uint8_t i = 0; i < BITS_IN_PDI_FRAME; i++)
 	{
 		/* Wait for a full cycle of the clock */
 		while (PIND & (1 << 5));
@@ -299,7 +298,7 @@ void PDITarget_SendBreak(void)
 
 	/* Need to do nothing for a full frame to send a BREAK */
 	SoftUSART_Data     = 0x0FFF;
-	SoftUSART_BitCount = BITS_IN_FRAME;
+	SoftUSART_BitCount = BITS_IN_PDI_FRAME;
 #endif
 }